In the context of a peripheral blood smear showing single, round, blue inclusions on Wright stain, what do Howell-Jolly bodies indicate?

Howell-Jolly bodies are small, round, blue inclusions found within red blood cells, which can be visualized using a Wright stain. These inclusions represent remnants of nuclear DNA that should normally be removed by the spleen. The presence of Howell-Jolly bodies typically indicates a failure of the spleen to filter out these residual nuclear fragments, which is most commonly seen in individuals who have undergone splenectomy.

The spleen plays a critical role in the removal of these inclusions as part of its function in clearing old or damaged red blood cells from circulation. When the spleen is absent or nonfunctional, such as after surgical removal or in certain pathological conditions affecting the spleen, Howell-Jolly bodies can accumulate in the peripheral blood, serving as a hallmark of splenic dysfunction or absence.

Thus, the presence of Howell-Jolly bodies on a peripheral blood smear strongly suggests a history of splenectomy or an abnormality of splenic function, aligning well with the correct answer.